Die holder assembly

ABSTRACT

The present invention relates generally to improvements in die holder assemblies, and more particularly to novel and practical improvements in the design of die holder assemblies which are employed to swage or pinch point screw blanks and the like. An embodiment of the invention disclosed herein includes a pair of relatively shiftable unitary assembly sections or heads having upper die holder accommodating cavities. The lower portions of said heads accommodate ram members which guide the heads in the horizontal relative shifting thereof. Novel means is provided for securing a die holder in said cavity in such a manner as to facilitate the ease with which a die holder may be attached to or disengaged from said heads.

United States Patent [191 Sygnator DIE HOLDER ASSEMBLY [75] Inventor: Henry Anton Sygnator, Arlington Heights, ll].

[73] Assignee: Illinois Tool Works Inc., Chicago,

Ill.

[22] Filed: Oct. 5, 1972 [21] App]. No.: 295,149

[52] US. Cl 10/2, 10/9, 10/21, v 72/475 [51] Int. Cl. 821g 3/16 [58] Field of Search 10/4, 9, 10,21, 24, 31,

lO/27, 40, 35, 42, 34, 53, 61, 70,11R, 12 R, l2.5, 15, 59, 2; 72/462, 470, 475, 413, 481

[56] References Cited 7 UNITED STATES PATENTS 1,546,9l4 7 /l925 Calkins.i 10/9 2,205,507 6/l940 Wilcox... l0/l2.5 3,109,187 ll/l963 Pirc l0/53 X 3,234,572 2/l966 Roser l0/50 3,398,413 8/1968 Skierski lO/9 [451 Junell, 1974 lO/l968 2/l97l Hall l0/24 X Dom et al. l0/l2 T Primary Examiner-Charles W. Lanham Assistant Examiner-Donald M. Gurley Attorney, Agent, or Firm-Olson, Trexler, Wolters, Bushnell & Fosse, Ltd.

[5 7] ABSTRACT The present invention relates generally to improvements in die holder assemblies, and more particularly to novel and practical improvements in the design of die holder assemblies which are employed to swage or pinch point screw blanks and the like. An embodiment of the invention disclosed herein includes a pair of relatively shiftable unitary assembly sections or heads having upper die holder accommodating cavities. The lower portions of said heads accommodate ram members which guide the heads in the horizontal relative shifting thereof. Novel means is provided for securing a die holder in said cavity in such a manner as to facilitate the ease with which a die holder may be attached to or disengaged from said heads.

3 Claims, 7 Drawing Figures DIE HOLDER ASSEMBLY SUMMARY OF THE INVENTION In die assembling apparatus of the general type contemplated by the present invention, certain problems have heretofore been experienced. For example, in die holder assemblies heretofore available the rigidity of the relatively shiftable assembly sections or heads which accommodate the die holders has not been adequate to assure absolute horizontal alignment of said heads during repetitive cycles of operation. Also, it has heretofore been necessary to dismantle various parts of the assembly in order to attach or detach a die holder with respect to the die accommodating cavities in the heads.

It is therefore an important object of the present invention to provide a die holder assembly which will solve the designated above mentioned problems or disadvantages.

More specifically, the present invention contemplates the provision of novel means for clamping a die holderagainst the shelf of complementary assembly heads. I i

It is'a further obje'ctof the present invention to so design said dieholder'clamping means as-to enable the attachment or removal of a die holder with a minimum of effort and without the necessity of dismantling the assembly apparatus.

The present invention further contemplates the provision of exceptionally rigid die holder accommodating heads, and to this end it is proposed to employ heads or sections of integral design whereby positively to preclude any distortion of said head during the metal working cycles of operation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 4 is a fragmentary side elevational view of the die holder assembly section or head, said view being taken substantially along the line 4-4 of FIG. 2;

FIG. 5 is a fragmentary horizontal sectional view taken substantially along the line 55 of FIG. 4;

FIG. 6 is a fragmentary side elevational view similar to FIG. 4 illustrating the manner in which die members or blocks of varying size may be accommodated; and

FIG. 7 is a fragmentary vertical sectional view of the device illustrated in FIG. 6 as it would appear if taken substantially along the line 77 of FIG. 5.

DESCRIPTION OF AN EMBODIMENT OF THE INVENTION Referring now to the drawings more indetail wherein like numerals have been employed to designate similar parts throughout the various views, it will be seen that one embodiment of a die holder assembly arrangement is designated generally by the numeral 10. The assembly 10 includes a stationary section or head 12 and a complementary horizontally shiftable section or head 14. Ram members or guides 16 and 18 are secured at the right extremity thereof, FIGS. 1 and 3, within the shiftable head 14. The portions of the guides 16 and 18 which project horizontally from the head 14 are longitudinally shiftable within complementary bushings or sleeves 20 and 22, respectively, mounted within the fixed section or head 12. Particular attention is directed to the fact that heads 12 and 14 are each of integral construction, head 12 being secured in a fixed position to a machine frame 24 by means of bolts 26, and the head 14 being secured to a horizontally shiftable I machine element 28 by means of a bolt 30..

prised of a back element 42, side elements 44 and 46,.

and a bottom portion 48. The side portions 44 and 46,

- together with the back portion 42 are clamped against the vertical surface 34 of the head 12 by means of suitable bolts 50.

Particular attention is directed to the manner in which the lower portion 48 of the die holder 40 is clamped against the shelf surface 32. This is accomplished by the use of a bolt 52 which'extends vertically through the lower die portion 48 and into the head 12, as clearly illustrated in FIG. 3. The upper surface of the die holder portion 48 is countersunk or recessed to accommodate the head of the bolt 52. A die member or block 54 is secured in position within the die holder by a set screw 56. By simply removing the die member'54, the upper head extremity of the screw 56 is exposed for accommodating a conventional screw turning tool (not shown).

The head 14 supports a die holder and die block cor-, responding structurally with the previously described die holder and die supported by the head 12. Hence, the elements of the die holder and associated parts supported by the head 14 are identified with numerals corresponding with the numerals previously employed to designate the elements carried by the head 12, but

bearing the suffix a. Each of the die members 54 and 54a are identical and when movedtogether serve to swageor pinch point the entering extremity of a screw blank 58, designated by dot-and-dash lines in FIG. 3.

In FIG. 7, the manner in which a die member of a size differing from the die member 54 may be mounted in the die holder 40 is shown. The die member in FIG. 7 is designaed by the numeral 54b and is less in thickness than the previously mentioned die member 54. A hardened filler block 60 is positioned between the back of the die member 54b and the front side of the die holder element 42. The filler member 60 is held against the die holder member 42 by means of a screw'member 62. From the foregoing description, it will be noted that the die holder centering bolts or dowel pins 52 and 520 are relatively long. Any forces resulting from the coaction of the die members 54 and 54a must be resisted by the sections or heads 12 and 14 in the vicinity of their respective'shelves 32 and 32a. In other words, should this area of the heads 12 and 14 experience distortion as the result of the above mentioned coaction, there would be atendency to shear the centering bolts or dowel pins 52 and 52a. By having these shelves supported in the manner disclosed, distortion of the heads is completely avoided. In this connection, it will be noted that the portion of the heads supporting their respective shelves is formed integral with the remainder of each head. The integral portion of the head 12 which supports the shelf '32 thereof completely encircles the sleeves -22 accommodating the' horizontally shiftable guide members or rams 16,-18, respectively. The

ram supporting portion of the head 12 is relatively large in diameter and long enough to provide complete surface contact at all times of the guide members 16 and 18 with the inner surface of the fixed sleeves 20 and 22, respectively. in this manner, cantilever forces tending to distort the head 12 are precluded,

As previously mentioned, in order to expose thehead extremity of the die holder centering bolts or dowel pins, it is only necessary to remove the die member associated therewith. This should be clearly distinguished from the die assembly devices heretofore available, wherein it was necessary to remove the fly wheel, slide cover, etc.,from behind the die jaws, in order to render the centering bolt accessible. in applicants above described die assembly, the centering bolts are accessible through the throat of the machine, thereby avoiding the necessity of the above mentioned tedious and timeconsuming disassembly of fly wheels, etc.

While for purposes of disclosure one embodiment-of the invention has been described herein, it should be understood that the present invention contemplates structural modifications and changes coming within the scope of the appended claims.

l'claim:

1. A die holder assembly for use in an open throat machine for forming the extremities of metal screw blanks with complementary dies positioned and precisely retained in die holder means for accurately pinching the extremities of the screw blanks by relative reciprocation of the complementary dies in a direction transverse the axis of the screw blanks, including a pair of sectionsfor accommodating horizontally disposed guide means at the lower portions thereof, the upper portion of each section having a die holder means accommodating cavi y, die holder means including removable horizontally disposed bottom portions in each of said cavities, horizontally disposed shelf means integral with each section and defining the lower portion of each of said cavities and providing a support for the bottom portion of complementary die holder means, the shelf means for the pair of sections being horizontally aligned to insure precise alignment of mating forming cliesv in the die holder means, the bottom porthe integral shelf means of a corresponding section, an elongate fastener member extending through the aperture in each of said bottom portion of the die holder means and into the aligned aperture of said corresponding section, the elongate fastener member clampingly retaining the bottom portion of the die holder means against the shelf means against movement in the vertical direction thus providing a pair of horizontal surfaces capable of being accurately machined to support the dies and which retain their alignment during repeated removal and replacement of dies as well as during successive forming strokes of the open throat machine, the upper extremities of said fastener members being exposed within complementary die holder means and provided with turning tool accommodating means, each die holder means further including vertical back elements, said bottomand back elements providing intersecting alignment surfaces to hold the complementary dies in their aligned positions, said guide means including guide shafts associated with the lower portions of said sections, one of said sections being adapted for mounting in a fixed position and the other being horizontally reciprocable, one extremity of said guide shaft being secured within saidreciprocable section, the opposite extremity of said guide shaft being horizontally reciprocable within the other section, each section having an integral portion positioned immediately beneath and defined by a generally vertical wall which extends downwardly from the free extremity of the shelf means thereof, the lower portions of the sections encircling said guide shafts, to provide rigid support means for the shelf means and die holder means directly beneath thereof, the lower portion of the fixed section having a dimension in a direction longitudinal of the guide shafts great enough to assure that the guide shafts will penetrate substantially therethrough and be in frictional contact therewith during cycles of reciprocation thereof, the integral shelf and bottom portion of the die holder means having an area great enough to completely support the mating bottom surfaces of the associated dies.

2. A die holder assembly as set forth in claim 1 wherein a vertical wall surface extends upwardly from tion of each of said die holder means being completely traversed by a vertically extending aperture adapted for alignment with a complementary aperture opening into said shelf means and integral therewith and elongate horizontally disposed threaded fastener members serve to clampingly engage said vertical back elements of said die holder means against said vertical wall surface.

3. A die holder assembly as set forth in claim 1 wherein the shelf supporting portion of said fixed section presents relatively thick walls encircling said guide shaft whereby to contribute to the rigidity of said section in that vicinity and to counteract cantilevering forces.

Disclaimer 3,8l5,166.Hen 7" 2 Anton Sy gnator, Arlington Heights, Ill. DIE HOLDER vASSEMBLY. Patent dated June 11, 1974. Disclaimer filed Aug. 16, 1978, by the assignee, Illinois Tool Works Inc.

Hereby enters this disclaimer to all claims of said patent.

[Oyfioz'al Gazette Octobm 24, 1.978.] 

1. A die holder assembly for use in an open throat machine for forming the extremities of metal screw blanks with complementary dies positioned and precisely retained in die holder means for accurately pinching the extremities of the screw blanks by relative reciprocation of the complementary dies in a direction transverse the axis of the screw blanks, including a pair of sections for accommodating horizontally disposed guide means at the lower portions thereof, the upper portion of each section having a die holder means accommodating cavity, die holder means including removable horizontally disposed bottom portions in each of said cavities, horizontally disposed shelf means integral with each section and defining the lower portion of each of said cavities and providing a support for the bottom portion of complementary die holder means, the shelf means for the pair of sections being horizontally aligned to insure precise alignment of mating forming dies in the die holder means, the bottom portion of each of said die holder means being completely traversed by a vertically extending aperture adapted for alignment with a complementary aperture opening into the integral shelf means of a corresponding section, an elongate fastener member extending through the aperture in each of said bottom portion of the die holder means and into the aligned aperture of said corresponding section, the elongate fastener member clampingly retaining the bottom portion of the die holder means against the shelf means against movement in the vertical direction thus providing a pair of horizontal surfaces capable of being accurately machined to support the dies and which retain their alignment during repeated removal and replacement of dies as well as during successive forming strokes of the open throat machine, the upper extremities of said fastener members being exposed within complementary die holder means and provided with turning tool accommodating means, each die holder means further including vertical back elements, said bottom and back elements providing intersecting alignment surfaces to hold the complementary dies in their aligned positions, said guide means including guide shafts associated with the lower portions of said sectIons, one of said sections being adapted for mounting in a fixed position and the other being horizontally reciprocable, one extremity of said guide shaft being secured within said reciprocable section, the opposite extremity of said guide shaft being horizontally reciprocable within the other section, each section having an integral portion positioned immediately beneath and defined by a generally vertical wall which extends downwardly from the free extremity of the shelf means thereof, the lower portions of the sections encircling said guide shafts, to provide rigid support means for the shelf means and die holder means directly beneath thereof, the lower portion of the fixed section having a dimension in a direction longitudinal of the guide shafts great enough to assure that the guide shafts will penetrate substantially therethrough and be in frictional contact therewith during cycles of reciprocation thereof, the integral shelf and bottom portion of the die holder means having an area great enough to completely support the mating bottom surfaces of the associated dies.
 2. A die holder assembly as set forth in claim 1 wherein a vertical wall surface extends upwardly from said shelf means and integral therewith and elongate horizontally disposed threaded fastener members serve to clampingly engage said vertical back elements of said die holder means against said vertical wall surface.
 3. A die holder assembly as set forth in claim 1 wherein the shelf supporting portion of said fixed section presents relatively thick walls encircling said guide shaft whereby to contribute to the rigidity of said section in that vicinity and to counteract cantilevering forces. 